UNIT 3 past papers

Question 1

suggest why the nucleic acid molecule must be damaged in a virus used
in a vaccine.

Answer 1

to prevent the virus from replicating

Question 2

Explain why the surface proteins of the virus used in the vaccine must
remain undamaged.

Answer 2

the surface proteins act as antigens
which triggers an immune response

Question 3

Explain the importance of presenting the data as the number of
stroke patients per 100 000.

Answer 3

allows groups of different sizes to be compared

Question 4

Paralysis occurs when voluntary muscle is unable to contract.
Explain how a stroke could lead to muscle paralysis on the left side of the body.

Answer 4

lack of oxygen will kill the brain tissue
and the right side of the brain would be damaged

Question 5

using evidence from a bar graph suggest why the drug was not worth further development

Answer 5

the error bars overlap
there is no significant difference between the group results

Question 6

Explain how the diagram supports the suggestion that there is localisation of function in the brain.

Answer 6

different areas of the brain are active during different parts of the task

Question 7

explain why displacement occurs

Answer 7

short term memory has a limited capacity

Question 8

give a reason why increased blood flow to the infection site is beneficial in stopping the infection

Answer 8

increases the number of phagocytes

Question 9

Describe what happens during apoptosis

Answer 9

production of self destructive enzymes

Question 10

Give examples of contextual cues to aid recall

Answer 10

same environment
the people that are there
the clothes that were worn

Question 11

how might a neuron in a new born child differ from an adult

Answer 11

has less myelin sheath

Question 12

state the function of the motor area in the left cerebral hemisphere

Answer 12

controls movement in the right side of the body

Question 13

which division of the nervous system is linked to the medulla

Answer 13

ANS

Question 14

Explain why vaccination against one virus would not provide immunity against another virus

Answer 14

antigenic variation
the antibodies are specific to one virus

Question 15

State the function of mitochondria in neurotransmission

Answer 15

provides energy to release neurotransmitters

Question 16

explain how the presence of phagocytes is important in the activation of T lymphocytes

Answer 16

phagocytes engulf the pathogen
and display the pathogens antigens on their surface

Question 17

Parkinson’s disease is associated with a loss of dopamine-producing
neurons in the brain. It cannot be treated by taking dopamine.
Describe a possible mode of action of a drug that could be used to treat this disease.

Answer 17

mimics the action of dopamine

Question 18

Describe how dopamine reinforces smoking behaviour

Answer 18

dopamine induces feelings of pleasure

Question 19

explain why vaccination against polio would not provide immunity against the influenza virus

Answer 19

polio and the influenza virus have different antigens

Question 20

Name the level of memory involved when students first saw and heard information on the heart

Answer 20

sensory

Question 21

Explain why vaccines do not cause disease in vaccinated individuals

Answer 21

the vaccine contains weakened pathogens

Question 22

Name the chemicals which aid the movement of T lymphocytes to the site of infection

Answer 22

cytokines

Question 23

Name the model that is used to explain the ability of the STM to perform simple cognitive tasks

Answer 23

working memory

Question 24

recalling the events that occurred when information was encoded into LTM can help the later retrieval of the information
name the term used to describe these events

Answer 24

contextual cues

Question 25

myelin sheath develops from birth to adolescence. Describe why this development allows children to become more coordinated as they get older.

Answer 25

it increases the speed of impulses

Question 26

describe the mechanism of action of B lymphocytes against pathogens

Answer 26

B lymphocytes have receptors which recognise antigens on pathogens they form a clonal population B lymphocytes produce antibodies. Antibodies bind to antigens on the pathogen.

Question 27

A new influenza vaccine is developed every year. Explain why this is required to protect the body from the influenza virus.

Answer 27

antigenic variation occurs so memory cells are not effective against the different antigen

Question 28

Describe the main events that occur in clonal selection

Answer 28

lymphocytes have a single type of membrane receptor specific to one antigen antigen binding leads to lymphocytes repeatedly dividing causing a clonal population of identical lymphocytes

Question 29

Cocaine is a recreational drug that has an effect at this synapse. Cocaine binds to the dopamine re-uptake proteins. As a result, the reward pathway is stimulated for longer. Suggest how cocaine produces this effect

Answer 29

dopamine blocks the reuptake proteins dopamine remains in the synapse

Question 30

explain why non functional LDL receptors can lead to an individual having high blood pressure

Answer 30

cholesterol will not be transported from the liver to body cells resulting in atherosclerosis

Question 31

describe how a virus is able to attach to a cell

Answer 31

the cell has membrane receptors that are specific to the virus

Question 32

Suggest a possible role of the nucleus in the transfer of information across a synapse

Answer 32

DNA codes for receptors